Heart of Eon by Anna Hackett

Okay, maybe hijacking an alien commander’s warship wasn’t her best idea…
Genius computer geek Wren Traynor prefers her high-tech comp lab to socializing with people, and she definitely prefers it over crawling through the bowels of the huge Eon warship she’s hijacked. When Earth’s Space Corps blackmails her into this deadly mission, Wren will do anything to help her beloved sisters and save the Earth from invasion by the insectoid Kantos aliens. That includes entering into a dangerous game of cat and mouse with the tall, hunky, and seriously enraged Eon war commander who captains the Rengard.
War Commander Malax Dann-Jad is a born protector and has forged a successful career in service to the Eon Empire. Haunted by an early mission where he lost good warriors, he’s dedicated to protecting his ship and its crew. Especially since his warship is carrying a special, top-secret cargo. But one tiny, infuriating Terran puts all that at risk when she commandeers his ship and refuses to listen to reason.
When the ravenous Kantos set their sights on the Rengard–using sneaky, underhanded tactics–Malax finds himself with an armful of curvy woman. He and Wren must join forces to fight back, and are shocked at their improbable, intense attraction. But with lives at risk, both will learn that strength comes in more ways than one and love can hit when you least expect it, and that in order to survive, you have to put everything on the line.